class Test: 
def init(self,a,b): 
self._c = {“c”:a+b} 
@property 
def c(self): 
return self._c 
@c.setter 
def c(self,value): 
self._c = value 
def get_num(self,d):
    self.c["d"]=d

c.setter不是给变量赋值吗，为何会修改字典中单个key的值。